Oil pressure drop after addition of OEM Oil Cooler?

I just finished a build of many replacements and upgrades - documented here. One of the upgrades was the addition of an OEM-style engine oil cooler. I.e. I removed the block off plate, added a set of Dorman replacement lines, and replaced the radiator with a new Denso OEM-style that had the provisions for oil cooler. Great addition in my book, but now my oil pressure is lower. I went from just below 40 psi @2000 rpm, fully warm, to around 30 psi, same conditions. Is that expected? Other than an oil and filter change (same grade and brands as before: Costco synth 5w-30, AC Delco PF63) I didn't change or do anything else that should affect oil pressure.

Any concerns with oil pressure maxing out at around 30-33 psi. I think hot idle is around 15 psi. I have a new spare screen that goes below the oil press sender. I think I will try putting that in first to see if it helps.

Seems like my pressure might have dropped ~2psi possibly after adding filter. (Could be in my head)

Pressures seem ok, but if you're sure it's dropped almost 10psi..
Make sure none of the hoses are kinked.. They are pretty short so that is unlikely I suppose..

huh.. I don't have any reference because I've not added one, but the thing I've seen on other gm cars with a oil cooler is they have a relief valve in the aluminum block that mounds above the oil filter to the engine block. did you happen to notice if your Dorman set had this. I'll try to look up a pic but if I'm remember right, at high flow rates when the restricting get above 7psi it allows it to bypass the cooler.



I don't know what the Tahoe might have stock setting. if you look at the block in this pick is the little screw in part on the back side.

Strange that it would happen "after the cooler lines installed". I have heard bad things about the AC Delco PF63. Yes, replace the screen and see what happens. I also had not thought about this and maybe I am over thinking, do you need a bit more oil for the lines capacity?

j91z28d1 said:

huh.. I don't have any reference because I've not added one, but the thing I've seen on other gm cars with a oil cooler is they have a relief valve in the aluminum block that mounds above the oil filter to the engine block. did you happen to notice if your Dorman set had this. I'll try to look up a pic but if I'm remember right, at high flow rates when the restricting get above 7psi it allows it to bypass the cooler.

05-13 Engine Oil Cooler Hose Assembly

05-13 Engine Oil Cooler Hose Assembly

www.zip-corvette.com

I don't know what the Tahoe might have stock setting. if you look at the block in this pick is the little screw in part on the back side.

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There's no adjustment valve on an OE one.

Dang that's expensive, guess it's a vette thing, lol. More than likely because of the valve?

A GM oil cooler line from RockAuto is $67

gooffeyguy said:

There's no adjustment valve on an OE one.

Dang that's expensive, guess it's a vette thing, lol. More than likely because of the valve?

A GM oil cooler line from RockAuto is $67

View attachment 436685

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if that's they truck link, the valve there. arrow pointing to it.

but yes. the vette tax is real.

and annoying haha.

OR VietVet said:

Strange that it would happen "after the cooler lines installed". I have heard bad things about the AC Delco PF63. Yes, replace the screen and see what happens. I also had not thought about this and maybe I am over thinking, do you need a bit more oil for the lines capacity?

Click to expand...

Will do on the screen - next on the list. I remember on my '09 Tahoe, the PF63 actually improved oil pressure. And that one had the oil cooler from factory. I like the PF63 since it has more capacity. But I have a PF48E laying around that I could install just to see if it helps? Or do you recommend a different brand? I know some on here prefer Wix. Yeah, adding the cooler and lines (and taller filter) I'm at 6.5-7 quarts for the first oil change. I'm sure next one will be less.

j91z28d1 said:

if that's they truck link, the valve there. arrow pointing to it.

Click to expand...

I used a Dorman set for the lines. I'm not sure why I didn't go with the GM ones, wish I would have now. But the Dorman does have that same valve. Should I try and adjust?

far as I know there's no adjustments. I was just thinking it might not have it at all.

if you're really curious there's a test port on the drivers side of the block in the front. you could test the oil pressure right off the pump and then compare it to the sensor port up tops with a mechanical gauge.

DaveO9 said:

Will do on the screen - next on the list. I remember on my '09 Tahoe, the PF63 actually improved oil pressure. And that one had the oil cooler from factory. I like the PF63 since it has more capacity. But I have a PF48E laying around that I could install just to see if it helps? Or do you recommend a different brand? I know some on here prefer Wix. Yeah, adding the cooler and lines (and taller filter) I'm at 6.5-7 quarts for the first oil change. I'm sure next one will be less.

I used a Dorman set for the lines. I'm not sure why I didn't go with the GM ones, wish I would have now. But the Dorman does have that same valve. Should I try and adjust?

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I am a WIX fan. The shorter AC Delco filter will just build oil pressure quicker but have less filtering capacity. I just like WIX over AC Delco when it comes to oil filters.